Ice-breaking system for ships

ABSTRACT

A system for making navigable channels through heavy sea-ice, comprising a ship carried, compressed-air operated, water-thrust actuated vertical ram for positioning beneath the water to break sea-ice by powered upward impacts with the under surface of the ice, accompanied by water-hammer ice shattering action, interspersed with powered descents, in rapid oscillation; a coacting spray suppressant curtain and a spray suppresant underwater thrust exhaust are disclosed, as well as an inertiaslug valve design in one embodiment to further the ice breaking efficiency.

United States Patent Wagner 1 Oct. 17, 1972 [54] ICE-BREAKING SYSTEM FOR SHIPS 3,130,701 4/1964 Langballe ..1 14/40 [72] Inventor: Jacob C. Wagner, PO. Box 133 New Castle, New Castle, Del. 19720 m Exammer-Trygve 511K [22] F] d M [I2 1971 Attorney-John F. McClellan, Sr.

1e arc 21] Appl. No.: 120,271 RA Application Data A system for making navigable channels through heavy sea-ice, comprising a ship carried, compressedcommuatlon'ln'pafl of 5 March air operated, water-thrust actuated vertical ram for 1970- positioning beneath the water to break sea-ice by powered upward impacts with the under surface of the [52] US. Cl. ..ll4/40 ice accompanied by watephammer ice shattering [51] lnLCl. ..B63b 35/08 tion, interspersed i h owered descents, in rapid [58] Field of Search ..114/40-42 Oscillation; a cmaeting spray suppressant curtain and a spray suppresant underwater thrust exhaust are dis- [56] References C'ted closed, as well as an inertia-slug valve design in one UNITED STATES PATENTS embodiment to further the ice breaking efficiency.

Wood ..114/40 12 Claims, 7 Drawing Figures PATENTED BT i 3.698 340 sum 1 or 2 INVEN TOR.

dAgOB C. WAGNER ATTORN E Y ICE-BREAKING SYSTEM FOR SHIPS This application is a continuation in part of my copending application for US. Pat. Ser. No. 16,516 filed Mar. 4, 1970, for ICE-BREAKING HAMMER AT- TACI-IMENT FOR SHIPS.

This invention relates to shipping channel sea-ice breaking generally and specifically to a system for equipping ships to open their own channels through very heavy ice, as for example, under the worst Arctic conditions. 7

In my above-referenced co-pending application for U. S. patent I describe the present urgent need for more efficient shipborne ice breakers to open channels for sea transport of oil from the Alaska north shore to more southerly ports.

lalso provide in that patent application a system for opening such sea-ice channels, which I feel to be far more effective than former devices and methods.

However, additional experimentation with ice-breaking mechanisms of the type described has led me to invent, design and develop a further class of mechanisms of extreme power and proven efficiency, one version of which I describe herein.

Objects of the present invention therefore are to provide an improved, flexibly adjustable ship-attached icebreaker capable of applying great localized breaking forces on the underside of ice floes and sheet ice with sufficient rapidity to allow the ship to proceed at moderate speed through the channel so provided.

I accomplish these and other objects with a massive hollow ram or hammer which is oscillated by compressed air acting on hydraulic columns bothupwardly and downwardly, in such manner as to produce a water-hammer effect on the upward stroke and reactive thrust up and down alternately.

As optional features, I provide alternative modes of pneumo-hydraulic action, and co-active flexible membrane means for preventing spray generated by the device from reaching the ship.

The above objects and advantages and others not specifically set forth herein will become apparent upon examination of the following description, including the drawings, in which:

FIGS. l-3 are side elevations showing the ice-breaking system of my invention in operation;

FIG. 4 is an elevation in section of a portion of my invention;

FIG. 5 is a detail of FIG. 4 modified, and

FIGS. 6 and 7 are details of further modifications based on the FIG. 4 embodiment.

Turning now to the Figures in detail:

FIGS. 1, 2 and 3 show my invention in use breaking ice in three positions of operation. Ship S supports the ice-breaking attachment 10 by means of arms 12 which are pivoted at 14 and 16. The arms are paired and are substantially symmetrically disposed about the long centerline of the ship. One or both of the arms serves as a compressed-air passageway connecting the ship S with the unit 10. The ship carries a high capacity source of compressed air, not shown, for supplying the unit through the arm or arms. This general arrangement is illustrated in more detail in my referenced co-pending application.

Provision is made for admitting ambient water to the ice-breaker interior. By means of high velocity displacement of water by compressed air the presently described ice breaker is driven alternately upward and downward with great force. Water jet outlets are indicated at 46 on the upper end of the device and at 54 at the lower end.

Because of the extreme icing conditions usually encountered near heavy ice, a means of effectively preventing spray and ice particles cast upward by this invention is provided in the form of screen 80. The screen is attached to the bow of the ship, overhanging the water ahead of the bow. The screen has a rigid, rectangular frame 82 supported by a pair of spaced stanchions 86, 88. The screen depends flexibly from the frame and consists of a roof and enclosing side curtains 84 to contain ice particles and spray. The screen may be of heavy, flexible fabric, and is preferably coated with Teflon or some other anti-adherent coating. The lower edges of the screen are preferably weighted, to prevent displacement by high winds.

- In FIG. 1 the icebreaker is at a low position, allowing it to be positioned below the ice. It will be seen that if this position is not low enough, so that the upper part of the device strikes the edge of ice as it advances, the unit 10 will simply pivot, avoiding damage. It is self-righting and self-restoring. If the unit is tipped over, air is spilled from a diving-bell-like buoyancy chamber which will be described later; the unit sinks, and, on being restrained by the pivots at a lower depth, assumes an upright position again because the pivot points are positioned considerably above the center of gravity. Air is then pumped into the buoyancy chamber to restore the mass trim by adjusting the displacement.

In FIG. 2, the unit has driven itself upward and is impacting against the ice.

In FIG. 3, the ice has been broken and thrust aside, and the ice-breaking unit is driving itself downward.

In the interval between the positions shown in FIG. 2 and FIG. 3, the ice-breaking action is assisted by the previously mentioned internal water-hammer effect in the ice-breaking unit which imparts a violent assist, shattering the ice at the crucial time.

These operations will be better understood from examination of FIG. 4.

FIG. 4 is a section taken along the long axis of the unit 10 and in a direction looking toward the ship.

The device shown comprises three operating chambers l, 2, and 3, plus a valve chamber 4; two sets of thrust tubes 20 and 22, and three control valve systems 24, 26, and 28. The chambers are enclosed by an outer housing which forms a domed enclosure 48 at the top, a midbody cylindrical portion 50 which is faired with the dome and is open at the bottom 52.

The chambers are divided by walls 56,58 and 60. Chamber 1 is preferably spheroidal as shown and heavily reinforced, as by open-cell metal honeycomb structure 61.

Compressed air is fed into chamber 1 through arms 12, as noted. Air is distributed to the upper tubes when required through two-way air valve 24, and ducts 62. Air is distributed to the lower tubes 22, when required, through the same air valve, 24, and through duct 64 which passes through bulkhead 58. If plural downward thrust tubes 22 are used, according to the preferred embodiment, the lower wall 60 of the chamber is a header or manifold for the upper ends of the tubes. The

chamber 3 within the housing below this manifold and through which these tubes pass, comprises a buoyancy chamber which at all times during operation of the device contains some volume of air. The volume of air within the buoyancy chamber is varied through operation of the valve 28, a three-way valve which connects chamber 3 with the upper part of chamber 2 through duct 66 or with the sea through duct 68, or, if necessary, connects chamber 2 directly with the sea, or both chambers 2 and 3 directly with the sea.

Braces 70 are provided as necessary for rigid mounting of the lower thrust tubes 22.

Operation of the ice-breaker is as follows:

Starting from the position of FIG. 1, all thrust tubes and chamber 2 are filled with water. All valves are closed except valve 24 which is opened admitting air to chamber 2, and forcing rapid downward displacement of the water in tubes 22, accelerating the unit upwardly. Prior to arrival of the unit at the position of FIG. 2, the impact position, valve 24 is closed and valve 28 is simultaneously opened, allowing all the air to pass from chamber 2 into chamber 3 or into the sea, or both, according to desired floatation trim at the moment.

Release of air pressure in chamber 2 allows water from the tubes 22 into the chamber, displacing the air. When the air is substantially displaced, valve 28 is closed, and the entering water is caused to lose momentum suddenly and to hammer against bulkhead 58. This helps to shatter the ice against which the device has by now impacted. As the device continues to rise, thrusting the shattered ice aside, the air in chamber 3 becoming less compressed, acts as an elastic body, aiding oscillatory action of the device.

At turnaround, valve 24 is opened into the upper jet tubes 20, forcing water upwardly from the tubes. The expelled water helps drive aside and further separate the ice above as it reactively drives the unit 10 downwardly.

As the unit descends valve 24 is closed and valves 26 are opened, flooding the upper tubes with water through the lower orifices 74. These valves are then closed, valve 24 is opened again, admitting air to chamber 2, and the cycle begins again.

Synchronization of operation of the device is preferably achieved through electrical means as fol lows. All valves are solenoid operated through leads (not shown) from shipboard which are passed through the hollow arms 12. Appropriate switches are actuated by a cycling timer having adjustable-relation cams for the respective switches, all aboard ship but not shown. An impact switch can be installed in the unit 10 as at 78, and impact then used as a fiducial point in the timing cycle by causing the program cycle to reset automatically at each impact, on signal.

FIG. 5, a side elevation in partial section, shows an optional embodiment of the FIG. 4 ice-breaker, having a solenoid operated water valve 90 at the upper end of each of the lower tubes 22. These valves may be operated simultaneously to check the flow of water in either direction. If all are shut simultaneously as the flow of water is upward, the force applied tends to accelerate the unit 10 suddenly in the upward direction. Conversely if the flow is downward and the valves are shut, force is suddenly applied in the opposite direction.

FIG. 6 is a side elevation detail in partial section of a check valve or floating impact valve 92, installed in similar location to the valves in FIG. 5. Each of the lower thrust tubes 22 in this embodiment may be equipped with one of these movable-slug -slug type valves. Operation of the valve is very similar to operation of hydraulic ram valves. When inflow of seawater reaches sufficient velocity past the valve body 94 which is centered by fins 96, 98, the valve body is surged upward from the ring-stop at the bottom and jammed against the tapered seat 102 above, closing the thrust tube. This automatically produces the hammerlike shock similar to that previously described, aided by the momentum of the valve body. The valve bodies may be very massive in view of the high rate of upward flow in the thrust tubes.

FIG. 7 is a detail of the FIG. 4 structure, modified as follows, to minimize spray when necessary. Provision is made as before to eject water upwardly from the thrust tubes 720 to drive the device down. However, as shown, an additional downward extension 721 of each thrust tube 720 is made, terminating in an upward recurve at orifice 774 to allow pressure through valve 726 to expel water in the proper direction from deep below the surface, minimizing spray while still performing the other functions.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

Iclaim:

1. An ice breaker system for ships, comprising: ram means for impacting ice vertically from beneath, means for movable attachment of the ram means to a ship, and means for driving the ram means both upwardly against the ice under power and downwardly away from the ice under power in rapid sustained oscillation, said means for driving the ram means including both upwardly oriented and downwardly oriented conduits, means for receiving ambient water into the conduits, and means for ejecting received ambient water upwardly and downwardly in alternation from the conduits.

2. An ice breaker system for ships comprising: ram means for impacting ice from beneath, said ram means including plural rigid compartments; means for driving the ram means both upwardly and downwardly under power including conduit means connected with a said compartment for admitting ambient water to the system, compressed air means connected to a said compartment for expelling the water admitted, and both upwardly ducted and downwardly ducted tubes connected with the compressed air means for deriving downward and upward thrust respectively from said water expulsion; and means for movable attachment of the ram means to a ship.

3. An ice breaker system for ships as recited in claim 2, wherein the means for movable attachment of the ram means to a ship comprise at least one arm adapted for pivotal attachment of the ram means to a ship to convey compressed air from shipboard to the ram means.

4. An ice breaker system for ships as recited in claim 3, wherein the plural compartments are vertically related, with the uppermost compartment comprising means for receiving and storing compressed air from the arm means, and having valve and conduit means associated therewith for distributing compressed air therefrom to at least one other of said compartments.

5. An ice breaker system for ships as recited in claim 4, wherein the plural compartments include an uppermost compartment, an intermediate compartment, and a lowermost compartment, with the lowermost compartment being open at the bottom in the manner of a diving bell, with the means for driving the ram means including at least one downwardly ducted thrust tube means extending from said intermediated compartment downwardly past said lowermost compartment, for thereby conveying and expelling ambient water from the intermediate compartment downwardly, under pressure, and with a said conduit means connecting the uppermost compartment with the intermediate compartment for thereby applying compressed air pressure to ambient water in the intermediate compartment.

6. An ice breaker system for ships as recited in claim 5, wherein the means for driving the ram means includes at least one upwardly directed thrust tube means adapted for passing water therethrough and wherein the compressed air conduit means includes connective with the lowermost compartment for expelling water therefrom for trimming the displacement of said ram means.

7. An ice breaker system as recited in claim 6, and a said valve means adapted to close the downwardly ducted thrust tube means during flow of ambient water through the downwardly ducted thrust tube means, for thereby transferring momentum from the water to the ram means.

8. An ice breakersystem for ships as recited in claim 7, wherein the uppermost compartment comprises a spheroidal chamber, with an upper wall of said chamber forming an impact structure for icebreaking by said system.

- 9. An ice breaker system for ships as recited in claim 8, wherein the spheroidal chamber is reinforced internally by honeycomb structure.

10. An ice breaker system for ships as. recited in claim 7, wherein the valve means adapted to close the downwardly ducted thrust tube means comprises an impact type valve having a movable-slug body and a seat above the movableslug body adapted for sealing contact with the movable-slug body, whereby momenturn of the movable-slug body is imparted to the ram means on closure of the valve by passage of fluid through the thrust tube means.

11. An ice breaker system for ships as recited in claim 5, wherein the means for driving the ram means includes at least one thrust tube extended downwardly and recurved upwardly at the duct, thereby adapting the thrust tube for expelling water upwardly beneath the surface of ambient water, suppressing spray.

12. An ice breaker system for ships as recited in claim 5, and means for containing spray, water and ice, said means for containing spray being adapted for coaction with the ram means and comprising an enclosure of flexible material having sides and a roof but open at the bottom, and a frame for supportively attaching the upper part of the enclosure to a said ship above the ram means, whereby spray, water, and ice thrown upward by the ram means are contained in said enclosure. 

1. An ice breaker system for ships, comprising: ram means for impacting ice vertically from beneath, means for movable attachment of the ram means to a ship, and means for driving the ram means both upwardly against the ice under power and downwardly away from the ice under power in rapid sustained oscillation, said means for driving the ram means including both upwardly oriented and downwardly oriented conduits, means for receiving ambient water into the conduits, and means for ejecting received ambient water upwardly and downwardly in alternation from the conduits.
 2. An ice breaker system for ships comprising: ram means for impacting ice from beneath, said ram means including plural rigid compartments; means for driving the ram means both upwardly and downwardly under power including conduit means connected with a said compartment for admitting ambient water to the system, compressed air means connected to a said compartment for expelling the water admitted, and both upwardly ducted and downwardly ducted tubes connected with the compressed air means for deriving downward and upward thrust respectively from said water expulsion; and means for movable attachment of the ram means to a ship.
 3. An ice breaker system for ships as recited in claim 2, wherein the means for movable attachment of the ram means to a ship comprise at least one arm adapted for pivotal attachment of the ram means to a ship to convey compressed air from shipboard to the ram means.
 4. An ice breaker system for ships as recited in claim 3, wherein the plural compartments are vertically related, with the uppermost compartment comprising means for receiving and storing compressed air from the arm means, and having valve and conduit means associated therewith for distributing compressed air therefrom to at least one other of said compartments.
 5. An ice breaker system for ships as recited in claim 4, wherein the plural compartments include an uppermost compartment, an intermediate compartment, and a lowermost compartment, with the lowermost compartment being open at the bottom in the manner of a diving bell, with the means for driving the ram means including at least one downwardly ducted thrust tube means extending from said intermediated compartment downwardly past said lowermost compartment, for thereby conveying and expelling ambient water from the intermediate compartment downwardly, under pressure, and with a said conduit means connecting the uppermost compartment with the intermediate compartment for thereby applying compressed air pressure to ambient water in the intermediate compartment.
 6. An ice breaker system for ships as recited in claim 5, wherein the means for driving the ram means includes at least one upwardly directed thrust tube means adapted for passing water therethrough and wherein the compressed air conduit means includes connective with the lowermost compartment for expelling water therefrom for trimming the displacement of said ram means.
 7. An ice breaker system as recited in claim 6, and a said valve means adapted to close the downwardly ducted thrust tube means during flow of ambient water through the downwardly ducted thrust tube means, for thereby transferring momentum from the water to the ram means.
 8. An ice breaker system for ships as recited in claim 7, wherein the uppermost compartment comprises a spheroidal chamber, with an upper wall of said chamber forming an impact structure for icebreaking by said system.
 9. An ice breaker system for ships as recited in claim 8, wherein the spheroidal chamber is reinForced internally by honeycomb structure.
 10. An ice breaker system for ships as recited in claim 7, wherein the valve means adapted to close the downwardly ducted thrust tube means comprises an impact type valve having a movable-slug body and a seat above the movable-slug body adapted for sealing contact with the movable-slug body, whereby momentum of the movable-slug body is imparted to the ram means on closure of the valve by passage of fluid through the thrust tube means.
 11. An ice breaker system for ships as recited in claim 5, wherein the means for driving the ram means includes at least one thrust tube extended downwardly and recurved upwardly at the duct, thereby adapting the thrust tube for expelling water upwardly beneath the surface of ambient water, suppressing spray.
 12. An ice breaker system for ships as recited in claim 5, and means for containing spray, water and ice, said means for containing spray being adapted for co-action with the ram means and comprising an enclosure of flexible material having sides and a roof but open at the bottom, and a frame for supportively attaching the upper part of the enclosure to a said ship above the ram means, whereby spray, water, and ice thrown upward by the ram means are contained in said enclosure. 